The use of fluids at a job site is well known, particularly in the oil and gas industry. Fluids commonly known as “drilling mud” are widely used for drilling bore holes. Fracturing fluids are used for hydraulic fracturing or “tracking” processes. Use of such fluids at a job site requires on-site fluid storage and delivery facilities. A variety of fluid storage tanks are commonly used for such purposes across various industries.
Fluid storage tanks may be horizontal or vertical, and may be constructed from a variety of materials. Steel tanks are commonly used, as are inflatable tanks that are more easily transported to a job site. Horizontal tanks, including inflatable horizontal tanks, tend to occupy a great deal of space, and this is not always desirable or practical at a job site. At sites where space is more limited, vertical tanks are commonly used.
Steel vertical tanks are common, typically having an inlet path allowing flow into the tank, and an outlet for allowing flow out of the tank. Such tanks are used individually, and when the tank and connections are fully assembled, the direction of flow to and from the tank is limited.
It is commonplace in drilling practices in the oil and gas industry to switch from water based drilling mud to oil based drilling mud. Conventional tanks must be cleaned by hand, with persons working inside the tank, to ensure removal of all water based drilling mud from the tank before oil based mud can be introduced into the tank. During the cleaning process, the remaining drilling equipment cannot be used and is simply on standby. The rental costs of such equipment on standby is significant.
Thus, it is an object of the invention to provide a vertical tank that can be combined with other vertical tanks to form a tank array that has more storage capacity than horizontal tanks. It is another object of the invention to provide a tank that is easier to clean in the field compared to conventional tanks in order to reduce equipment and labor standby costs. It is another object of the invention to provide a vertical tank that can be accessed from multiple points to insert or remove fluid from the same.